Injection-Molded Composite Construct

ABSTRACT

A frame is injection molded onto a group of panels to form a container. The panels extend at least partially around, and at least partially define, a cavity of the container.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of allowed U.S. patentapplication Ser. No. 13/357,295, filed Jan. 24, 2012, which is adivisional of U.S. patent application Ser. No. 11/715,718, filed Mar. 8,2007 (now issued as U.S. Pat. No. 8,124,201), which claims the benefitof both U.S. Provisional Patent Application No. 60/781,229, filed Mar.10, 2006, and U.S. Provisional Patent Application No. 60/834,402, filedJul. 31, 2006. The entire disclosures of all of the above-referencedpatent applications are incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention generally relates to composite constructs and,more particularly, the present invention relates to cartons withinjection-molded features.

A variety of constructs that are in the form of containers are known.There is always a desire for containers that provide a new balance ofproperties. For example, there is always a desire for improvementsrelating to a container that is lightweight, stiff (even when containinghot food), leakproof and cost-effective.

BRIEF SUMMARY OF SOME ASPECTS OF THE INVENTION

An aspect of the present invention is the provision of a construct, suchas a container or more specifically a tray, that can advantageously beboth lightweight and stiff (even when containing hot food), and that iscost-effective to produce. The container can also be leakproof. Inaccordance with one example of the present invention, the containerincludes a group of panels that is supported by a frame. The panels canbe at least partially formed from paperboard, and the frame can be atleast partially formed from polymeric material, so that the frame can bedistinct from the panels.

In accordance with one acceptable method, the frame can be injectionmolded at least partially onto and/or around the group of panels. Morespecifically, the group of panels can be arranged in a predeterminedconfiguration, so that the group of panels extends at least partiallyaround, and at least partially defines, at least one cavity of thecontainer. The frame can be mounted to (e.g., molded onto) at leastportions of some of the panels, so that the frame holds the group ofpanels in the predetermined configuration.

In accordance with one example of the present invention, corners of thecontainer are at least partially defined by some of the panels, and theframe advantageously extends into and seals the corners so that that thecontainer is substantially leakproof. The panels can be part of a webthat includes paperboard and a polymer film that is carried by thepaperboard. The polymer film and a polymer from which the frame isconstructed can be selected so that they firmly adhere to one another,such as during an injection-molding process. This firm adhesion betweenthe polymer film and the frame can advantageously enhance theleakproofness of the container. If desired, the leakproofness canadvantageously be enhanced by forming the corners of the container sothat the panels remain at least substantially unpleated proximate thecorners.

Optionally, microwave energy interactive material can be positionedbetween the paperboard and the polymer film carried by the paperboard,or a web of microwave energy interactive material can be placed over thepolymer film, or a microwave energy interactive material can beassociated with the container by way of other means. The microwaveenergy interactive material can enhance the cooking, heating, browningand/or crisping of a food item that is contained by the container whilethe container is in a microwave oven.

An aspect of the present invention relates to providing a construct bydisposing a substrate into a mold, and then injecting a moldingmaterial, such as but not limited to polymeric material, into the moldso that the molding material becomes fixedly attached to the substrate.For example and not limitation, the substrate can be paperboard,cardboard, paper, a sheet of polymeric material, or a laminate thatincludes one or more of these materials.

Another aspect of the present invention relates to closing a blank in aforming tool (e.g., mold) so that the blank is at least partiallyerected during the closing of the mold, and then injecting a moldingmaterial, such as but not limited to polymeric material, into the closedmold so that the molding material becomes fixedly attached to theerected blank. The solidified molding material that is fixedly attachedto the erected blank can be in the form of a frame that at leastpartially holds the erected blank in its erected configuration. Theframe together with the erected blank can be characterized as aninjection-molded composite construct. For example and not limitation,throughout this disclosure, a construct can be characterized as being(e.g., can be shaped to function as) a blank, container, carton, sleeve,tray, or the like.

In accordance with one aspect of the present invention, when the moldingmaterial is injected into the mold, the molding material forcespredetermined portions of the blank against the forming tool (e.g.,mold) and thereby forms, or at least enlarges, channels. The moldingmaterial flows in, and solidifies in, these channels.

Another aspect of the present invention relates to reinforcing aninjection-molded construct. In one example, the injection-moldedconstruct is formed from a polymeric material, and it is reinforced withpaperboard, or the like.

In accordance with one aspect of the present invention, a containerincludes panels that extends at least partially around and at leastpartially define a cavity of the container. These panels include a basepanel, a first side panel extending upwardly from the base panel, and asecond side panel extending upwardly from the base panel. Edges of thefirst and second side panels extend along the same elongate corner ofthe container such that a gap is defined between the edges of the firstand second side panels. In addition, an overlap exists between the edgesof the first and second side panels. An injection-molded structureextends along and at least partially defines the corner of thecontainer. The injection-molded structure obstructs the gap and at leastpartially covers the overlap. This can advantageously both strengthenand seal the container.

According to one aspect of the present invention, a container includes abase panel and side panels that extend upwardly from the base panel. Theside panels extend at least partially around and at least partiallydefine a cavity of the container. Multi-part flanges extend outwardlyfrom upper edges of side panels. Each multi-part flange typicallyincludes a lower flange that extends outwardly from the upper edge ofthe respective side panel, an upright panel that extends upright from anouter edge of the lower flange, and optionally also an upper flange thatextends outwardly from an upper edge of the upright panel. The uprightpanel can extend vertically or be inclined with respect to the vertical,and typically it is inclined outwardly (e.g., slightly outwardly). Aband is injection-molded onto upper surfaces of both the upper and lowerflanges. The force of the injecting of the molding material can at leastpartially bend/form the flanges, such as by forcing them against asurface of a mold, so that the flanges take on the shape of the subjectsurface of the mold. The band can advantageously strengthen the flangesand provide a smooth surface for sealing with a lid, cover, or the like.Typically, the band is thicker above the lower flange than it is abovethe upper flange, such that the lower flange advantageously partiallydefines a relatively large channel for having molding material flowtherein during the injection molding.

According to one aspect of the present invention, a panel at leastpartially defines an elongate corner of the container. The panelincludes a curved portion, and an outward surface of the curved portionof the panel defines an outwardly projecting protrusion of the panel.The outwardly projecting protrusion of the panel is elongate and extendsalong the corner (e.g., to define a rib). An inward surface of thecurved portion of the panel defines a recess that is elongate andextends along the corner. An injection-molded strip extends along and atleast partially defines the corner of the container. The strip includesan outwardly projecting protrusion that is elongate, extends along thecorner, and extends into the recess of the curved portion of the panel.Advantageously, this arrangement can help to strengthen the containerand help to provide a smooth interior surface of the container. Alsoadvantageously, the rib-like protrusions of the panels define relativelylarge channels for accommodating flowing molding material during theinjection molding. Also, the rib-like protrusions of the panels can beformed by the injected molding material forcing respective portions ofthe panels against respective surfaces of a mold, so that the respectiveportions of the panels bend and take on the shape of the respectivesurfaces of the mold.

In one aspect of the present invention, a container includes an elongatecorner, and panels of the container include a curved portion. An outwardsurface of the curved portion defines an outwardly bulbous portion(e.g., protrusion) of the panels. An inward surface of the curvedportion defines a substantially bowl-shaped recess. An injection-moldedstrip, which extends along and at least partially defines the corner ofthe container, includes an outwardly bulbous portion that extends intothe substantially bowl-shaped recess. The outwardly bulbous portion ofthe panels and the outwardly bulbous portion of the strip are positionedat a lower end of the corner. Advantageously, this arrangement can helpto strengthen the container and help to provide a smooth interiorsurface of the container. Also advantageously, the bulbous protrusionsof the panels define relatively large channels for accommodating theflowing molding material during injection molding. Also, the bulbousprotrusions of the panels can be formed by the injected molding materialforcing respective portions of the panels against respective surfaces ofa mold, so that the respective portions of the panels bend and take onthe shape of the respective surfaces of the mold.

In accordance with one aspect of the present invention, a blank includesa base panel and flaps that are respectively connected to and extendoutwardly from the base panel. A gap is defined between a first of theflaps and a second of the flaps. At least an inner portion of the gapbecomes wider farther from the base panel. The first and/or the secondflap has a protruding feature that has a reducing effect on how thewidth of the gap changes as a function of increased distance outwardlyfrom the base panel. These protruding features may overlap in aconstruct erected from the blank. Advantageously, the overlap canstrengthen the construct and/or the overlap can help to control the flowof the molding material during the injection molding.

In accordance with one aspect of the present invention, a constructincludes a laminate including a releasable adhesive positioned betweenand at least indirectly joining together a substrate and a polymer film.At least one injection-molded feature is at least indirectly joined tothe polymer film. Advantageously, the construct may be readily separatedinto separate parts (one or both of which may be recycled). Theseparating can include separating the substrate and the polymer filmfrom one another so that the injection-molded feature remains at leastindirectly joined to the polymer film.

One aspect of the present invention is the provision of an apparatus foruse in at least partially forming a container. The apparatus includes amold having a cavity with an elongate interior corner that extends intothe cavity. The interior corner includes an elongate central regionpositioned between elongate recesses. Advantageously, this configurationcan help in the formation of containers in the mold, such as containerswith ribbed corners, as discussed above. In addition or alternatively,the mold can be configured to help provide the above-discussed bulbousportions.

In accordance with one aspect of the present invention, a female moldincludes a cavity having a plurality of elongate interior corners thatextend into the cavity, and a male mold is provided for being insertedinto the cavity of the female mold. The male mold includes an outer moldand an inner mold that is movably mounted to the male outer mold formoving between an extended configuration and a retracted configuration.The male outer mold includes corners that extend at least partiallyaround the male inner mold while the male inner mold is in the retractedconfiguration. The corners of the male outer mold are for beingrespectively positioned in the interior corners of the cavity of thefemale mold when the male mold is inserted into the cavity of the femalemold, so that the plurality of corners of the male outer mold arerespectively positioned between the interior corners of the female moldand the male inner mold while the male mold is inserted into the cavityof the female mold. Advantageously, this can seek to eliminate theformation of parting lines.

In accordance with one example of a method of manufacturing, a blank isclosed in a forming tool, so that the blank is formed into a constructthat is at least partially contained in the closed forming tool. Theforming tool includes a male mold and a female mold, and the closing ofthe blank in the forming tool includes engaging a first part (e.g.,nose) of the male mold against a portion of the blank, thereafter usingat least the first part of the male mold to at least partially force theportion of the blank into a cavity of the female mold and therebypartially form the construct, thereafter engaging a second part (e.g.,base or outer part) of the male mold against a portion of the partiallyformed construct to further form the construct, and moving the firstpart of the male mold relative to the second part of the male at aperiod of time that occurs during the closing of the blank in theforming tool and is after the engaging of the first part of the malemold against the portion of the blank. This can advantageously allow theblank to be erected in stages.

In accordance with another example of a method of manufacturing, theforming of a construct within a forming tool includes arranging a firstpart of the construct and a second part of the construct so that thereis an overlapping relationship between the first part and the secondpart, and an edge of the first part is positioned between the secondpart and a channel. Then an injection-molded feature is formed on theconstruct. The forming of the injection-molded feature includes forcingmolding material into the channel, so that the molding material flowsalong the first part, then across the edge of the first part, and thenalong the second part. This can advantageously help to keep the moldingmaterial on the proper side of the construct.

Other aspects and advantages of the present invention will becomeapparent from the following.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following, reference is made to the accompanying drawings thatare listed below. The drawings illustrate exemplary embodiments of thepresent invention, and they are not necessarily drawn to scale.

FIG. 1A is a plan view of blank in a flat configuration, in accordancewith a first exemplary embodiment of the present invention.

FIG. 1B is a plan view of a representative portion of the blank of FIG.1A.

FIG. 2A is a schematic cross-sectional view of a laminate from which theblank of FIGS. 1A and 1B can be constructed.

FIG. 2B is a schematic cross-sectional view of another laminate fromwhich the blank of FIGS. 1A and 1B can be constructed.

FIG. 3 is a schematic, top plan view of a tray, wherein the tray isconstructed from the blank of FIG. 1A and a frame, in accordance withthe first embodiment.

FIG. 4 is a schematic, isolated perspective view of the frame of thetray of FIG. 3.

FIG. 5 is a schematic cross-sectional view of the tray of FIG. 3 takenalong line 5-5 of FIG. 3, with only the cross-section being shown, inaccordance with the first embodiment.

FIG. 6 is a schematic partial view that illustrates the exterior of arepresentative corner portion of the tray of FIG. 3, with the cornerportion being viewed generally from below.

FIG. 7A is a schematic view of the interior of a portion of the cornerof FIG. 6, with the upper portion of the tray having been cut away.

FIG. 7B is like FIG. 7A, except that the corner element of the framethat is shown in FIG. 7A has been removed.

FIG. 8A schematically illustrates a mold assembly in an openconfiguration, with the blank of FIG. 1 shown in dashed lines as beingassociated with the mold assembly, in accordance with the firstembodiment.

FIG. 8B is a schematic pictorial view of the mold assembly of FIG. 8A inan open configuration.

FIG. 9 is a schematic view looking into the cavity of the outer mold ofthe female mold of the mold assembly of FIGS. 8A and 8B, with a portionof the blank of FIG. 1 schematically shown in dashed lines as beingassociated with the outer mold of the female mold, in accordance withthe first embodiment.

FIG. 10A schematically illustrates the mold assembly of FIG. 8A in itsclosed configuration, in accordance with the first embodiment.

FIG. 10B is a schematic, isolated top plan view of a portion of arepresentative corner of the blank of FIG. 1 with side panels foldedupwardly as though the blank has been partially forced into the cavityof the female mold, in accordance with the first embodiment.

FIG. 10C is like FIG. 10B, except that the blank has been farther forcedinto the cavity of the female mold, and a longer protruding feature ofthe blank is engaged to, and therefore being folded by, the shoulder ofthe outer mold of the female mold, in accordance with the firstembodiment.

FIG. 11A schematically illustrates, by way of an arrow, molding materialflowing in a downstream direction through a representative channel inthe closed mold assembly, with the flowing material interacting with aportion of the blank of FIG. 1, in accordance with the first embodiment.

FIG. 11B is a cross-sectional view that schematically illustratesportions of the mold assembly interacting with a portion of the blank ofFIG. 1 and a portion of the frame of FIG. 4, in accordance with thefirst embodiment.

FIG. 12 schematically illustrates the tray of FIG. 3 containing food andclosed with a polymer film, in accordance with the first embodiment.

FIG. 13 is similar to FIG. 11B, except that it is for a second exemplaryembodiment of the present invention.

FIG. 14 is an isolated pictorial view of an outer mold of a male mold,in accordance with the second embodiment.

FIG. 15 is an isolated pictorial view of a nose unit of the male mold ofthe second embodiment.

FIG. 16 is a schematic plan view of blank in a flat configuration, inaccordance with a third exemplary embodiment of the present invention.

FIG. 17 is like FIG. 5, except, for example, that FIG. 17 is for thethird embodiment.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

In the following, exemplary embodiments of the present invention aredescribed in greater detail with reference to the above-mentioneddrawings, in which like numerals refer to like parts throughout theseveral views.

FIG. 1 illustrates a construct, namely a blank 22, that can be formed(e.g., cut) from laminates, such as the laminates 20, 20′ shown in FIGS.2A and 2B, in accordance with a first exemplary embodiment of thepresent invention. As best understood with reference to FIG. 1, theblank 22 includes a base panel 24 that is connected to intermediatepanels 26 by an inner fold line 28. The intermediate panels 26 arerespectively connected to side panels 30, which can also becharacterized as flaps, by intermediate fold lines 32. Flange portions34 a-34 d are respectively connected to the side panels 30 by outer foldlines 36. Each of the flange portions 34 a-34 d includes a pair ofclosely adjacent fold lines 38. The flange portions 34 a-34 d can becharacterized as being portions of the respective flaps/side panels 30.In one example, one or more of or all of the inner fold line 28,intermediate fold lines 32, outer fold lines 36, and closely adjacentfold lines 38 can be omitted from the blank 22, as will be discussed ingreater detail below.

The blank 22 defines corner gaps 40, each of which is somewhat V-shaped.In accordance with the first embodiment, each of the corner gaps 40 andassociated features are identical, except for orientation. That is andmore specifically, each of the gaps 40 and associated structures are asshown in FIG. 1B, or a mirror image of what is shown in FIG. 1B. Othercorner gap arrangements are also within the scope of the presentinvention.

FIG. 1B is an enlarged view of a portion of the blank 22 that includes arepresentative one of the corner gaps 40. The representative corner gapis defined by opposed, outwardly extending inner edges 41 f, 41 b, andopposed, outwardly extending end edges 90 f, 90 b (e.g., end edges ofthe flange portions 34 c, 34 a) that respectively extend from the inneredges. The end edges 90 f, 90 b respectively in conjunction with endsections of outer edges 43 f, 43 b define protruding features 44 f, 44b. An inner portion of the representative corner gap 40 is definedbetween the inner edges 41 f, 41 b so that the inner portion of the gapbecomes wider farther from the base panel 24. The end edges 90 f, 90b/protruding features 44 f, 44 b have a reducing effect on how width ofthe gap 40 changes as a function of increased distance outwardly fromthe base panel 24.

Angles Af, Ab are respectively defined between the inner edges 41 f, 41b and the end edges 90 f, 90 b. The angles Af, Ab are less than 180degrees so that that angles at least partially provide the reducingeffect on how the width of the gap 40 changes as a function of distanceoutwardly from the base panel 24. As shown in the figures, the anglesAf, Ab are obtuse angles. As alluded to above and in accordance with thefirst embodiment, the angles Af, Ab play a role in causing the width ofthe outer portion of the gap 40 to change at a lesser rate, as afunction of distance outwardly from the base panel 24, than the width ofthe inner portion of the gap. Also, the angles Af, Ab can be different.For example, in the first embodiment the angle Af is smaller than theangle Ab so that, with respect to extending outwardly from the basepanel 24, the end edge 90 f extends convergently with respect to thecenterline CL of the gap 40, whereas the end edge 90 b extendsdivergently with respect to the centerline of the gap. For each of theouter edges 43 f, 43 b, each of its end sections extend obliquely withrespect to its middle section. Other angles and arrangements fordefining the gaps 40 and protruding features 44 f, 44 b are also withinthe scope of the present invention. In an alternative embodiment of thepresent invention, the protruding features 44 f, 44 b are omitted.

As mentioned above, in the first embodiment the angle Af is smaller thanthe angle Ab. At least partially as a result of this difference in theangles Ab and Af, the protruding feature 44 f of the flange portion 34 cis longer than the protruding feature 44 b of the flange portion 34 a(e.g., the protruding feature 44 f extends farther into the respectivegap 40 than the protruding feature 44 b). Similarly and as bestunderstood with reference to FIG. 1: the protruding feature 44 e of theflange portion 34 b is longer than the protruding feature 44 a of theflange portion 34 a, the protruding feature 44 g of the flange portion34 d is longer than the protruding feature 44 c of the flange portion 34b, and the protruding feature 44 h of the flange portion 34 d is longerthan the protruding feature 44 d of the flange portion 34 c. Thesedifferences in the protruding features 44 a-44 h can be advantageouslyutilized, for example, when the blank 22 is erected, as will bediscussed in greater detail below.

As best understood with reference to FIG. 2A, a laminate 20 from whichthe blank 22 can be formed includes more than one layer, butalternatively the laminate can be replaced with a single ply ofmaterial, such as, but not limited to, paperboard, cardboard, paper or apolymeric sheet. In accordance with the exemplary embodiments of thepresent invention, the laminate 20 includes a polymer film 50 that issupported by, and secured to, a substrate that can be in the form ofcardboard, paperboard 52 or any other suitable material. Alternatively,the paperboard 52 and polymer film 50 can be replaced with any othersuitable materials, for example such that the substrate of the presentinvention is not limited to paperboard or the like. Nonetheless and inaccordance with the exemplary embodiments, the substrate typically is aclay-coated paperboard 52. As should be apparent, the paperboard 52 canbe more generally characterized as a substrate, and a suitable substratecan include paperboard with or without typical supplemental materials,such as coatings that can include clay coatings, colorants, indicia andthe like.

Optionally, and as shown in FIG. 2A, the polymer film 50 can be part ofa microwave interactive web 54 that is secured to the paperboard 52 by alayer of adhesive material 56. The web 54 can further include one ormore layers of microwave energy interactive material 58 that are securedto the polymer film 50 by one or more layers of adhesive material 60 orby any other suitable means. The microwave energy interactive material58 can be incorporated in the laminate 20/blank 22 to enhance orotherwise control the cooking and/or heating of a food item that iscontained by a container (e.g., tray 70 of FIG. 3) that is formed fromthe blank 22 and exposed to microwave energy. The optional web54/microwave energy interactive material 58 will be discussed in greaterdetail below.

Although the polymer film 50 is described above as being part of the web54, it is also within the scope of the present invention for the polymerfilm 50 to be adhered directly to the paperboard 54 by way of the layerof adhesive material 56 or by any other acceptable means, such that theone or more layers of microwave energy interactive material 58 andassociated adhesive materials 56, 58 are omitted. For example, the film50 can be extruded directly onto the paperboard 52 (i.e., via anextrusion coating process). In addition, the film 50 can be a coextrudedfilm, as schematically illustrated by the dashed line that is shown asdividing the film 50 in FIG. 2A. A variety of different types ofcoextrusions with differing numbers of layers and having layers withdifferent characteristics are within the scope of the present invention.For example, the various layers of the coextrusion can exhibit a widevariety of different properties such as, but not limited to, propertiesrelated to limiting oxygen and moisture transmission. Similarly, variousmarkings (e.g., pictures and/or text) and/or colors can be incorporatedinto, or deposited on, the film 50 or any other portion of the blank 22(FIG. 1) or tray 70 (FIG. 3).

If the microwave energy interactive material 58 is omitted, thecontainer (e.g., tray 70 of FIG. 3) formed from the blank 22 can betransparent to microwave energy. Nonetheless, such a container that istransparent to microwave energy can still be used in a microwave oven,and it may also be used in a conventional oven. If a container formedfrom the blank 22 is to be used in a conventional oven at hightemperatures, the materials from which the container is formed (e.g.,the materials from which the blank 22 is formed) would typically beselected so that they sufficiently withstand the high temperatures.

As should be apparent from the foregoing, a wide variety of laminates,from which the blank 22 can be formed, are within the scope of thepresent invention. For example and as described above and shown in FIG.2B, in a laminate 20′ from which the blank 22 can be formed, thelaminate 20′ can include the layer of adhesive material 56 positionedbetween and joining (either directly or indirectly) the polymer film 50(which can be in the form of one or more layers of polymer film, or thelike) to the substrate (e.g., paperboard 52). As discussed above and aswill be discussed in greater detail below, microwave energy interactivematerial 58 can optionally be associated with the polymer film 50.

Typically any web 54/microwave energy interactive material 58 is part ofthe laminate 20 before the blank 22 is cut from the laminate, or the web54/microwave energy interactive material 58 is fixed to the blank 22after the blank has been cut from the laminate 20′. Alternatively, themicrowave interactive web 54/microwave energy interactive material 58can be applied to or otherwise mounted to an already erected container(e.g., the tray 70 of FIG. 3). As one specific example, the microwaveinteractive web can be mounted (e.g., by way of an adhesive material,heat seal coating or any other suitable means) to interior surface(s) ofthe previously formed tray 70. In this regard, incorporated herein byreference is the entire disclosure of U.S. patent application Ser. No.11/715,556, filed Mar. 8, 2007.

In accordance with one example of the exemplary embodiments, theadhesive material 56 provides a bond with such a high peel strength thatthe polymer film 50, or more generally the web 54 (FIG. 2A), cannot beseparated from (e.g., peeled or stripped off of) the paperboard 52without pulling fibers, or groups of fibers, from the paperboard 52. Incontrast and accordance with another example of the exemplaryembodiments, the adhesive material 56 is a releasable adhesive materialthat provides a bond with a lower peel strength, so that the polymerfilm 50, or more generally the web 54 (FIG. 2A), can be more easilyseparated from (e.g., peeled or stripped off of) the paperboard 52, suchas without pulling fibers, or groups of fibers, (e.g., without pulling asubstantial amount of fibers) from the paperboard 52. Peel strength isdiscussed in ASTM D903-98 (2004) entitled “Standard Test Method for Peelor Stripping Strength of Adhesive Bonds”.

Typically, the adhesive material 56 will be selected/applied in a mannerso that it provides a peel strength that is sufficiently strong so thatthe polymer film 50/web 54 does not inadvertently become separated fromthe paperboard 52 at an undesirable time. In accordance with oneacceptable method of the exemplary embodiments, it is not desirable forthe polymer film 50/web 54 to separated from the paperboard 52 untilafter a user has finished using a construct (e.g., the tray 70 of FIG.3) that is at least partially formed from the laminate 20 or 20′, suchas for cooking food therein. For example and in accordance with oneacceptable method that can facilitate recycling of materials, when thetray 70 includes the adhesive material 56 that is in the form of areleasable adhesive, a user can manually separate (e.g., separate by theuse of his or her hands) the tray 70 by separating the paperboard 52from the polymer film 50/web 54. Typically an injection-molded feature,which can be in the form of a polymeric frame 72 schematically shown inisolation in FIG. 4, is adhered solely to the polymer film 50/web 54 andwill remain adhered to the polymer film 50/web 54, such that theadhesive bond between the 72 polymeric frame and the polymer film 50/web54 has a greater peel strength than the adhesive bond provided by theadhesive material 56 (e.g., between the paperboard 52 and polymer film50/web 54).

Typically a releasable adhesive material 56 will be selected that willprovide for substantially clean separation between the paperboard 52 andpolymer film 50/web 54, so that the separated paperboard 52 does notinclude any of, or significant remnants of, the polymer film 50/web 54,and the separated polymer film 50/web 54 does not include any of, orsignificant remnants of, the paperboard 52. In accordance with oneexample, the separated paperboard 52 and/or the separated polymer film50/web 54 (typically along with the polymeric frame 72 or the like stilladhered thereto) are recycled. Therefore, and in accordance with thisexample, the separated part not including “any of, or significantremnants of,” the other separated part means that the separated partsare sufficiently clean after separation so that they can be recycled ina conventional manner, without any more than the typical sorting and/orwashing that is typically required for post-consumer recycling.Recycling typically involves breaking something down and making itsuitable for reuse.

In addition or alternatively, for facilitating the releasing of theadhesive material 56 if desired, a release coating can be positionedbetween the adhesive material 56 and the paperboard 52 and/or polymerfilm 50/web 54, so that the release coating in combination with theadhesive material 56 enables separating the paperboard 52 and polymerfilm 50/web 54. In one example, such a release coating together with theadhesive material 56 can be cooperative so that the adhesive material 56(e.g., such as an adhesive material that is not typically releasablewithout the release coating) can be referred to as a releasableadhesive.

The adhesive material 56 and the above-discussed optional releasecoating that can be cooperative with the adhesive material 56 can bothbe selected from a wide variety of commercially available materials. Forexample and as discussed above, the adhesive material 56 can “in and ofitself” be a releasable adhesive material, such as a pressure sensitivereleasable adhesive material, a polar adhesive polymer that isreleasable (e.g., is not too polar), or the like or any combinationthereof. In one example, an acceptable adhesive material 56 may be Royal20164 or 20113 brand adhesive material, which is available from RoyalAdhesives and Sealants LLC of South Bend, Ind. If necessary or desired,those adhesive materials or other adhesive materials may be used afterthe application of a board primer. An acceptable board primer may beRoyal 20069 brand primer, which is also available from Royal Adhesivesand Sealants LLC.

In one example, the adhesive material 56 is a soluble adhesive (e.g., awater-soluble adhesive), so that the tray 70 (FIG. 3), or the like, maybe recycled by placing it in a bath that includes the appropriatesolvent (e.g., water) and optionally agitating, heating and/or otherwiseprocessing the bath to separate the paperboard 52 and polymer film50/web 54. In one specific example in which the adhesive material 56 isa soluble adhesive, such as a water-soluble adhesive, the separating mayoccur in a paper recycling plant, where the polymer film 50/web54/polymeric material may be separated from the paperboard 52/pulp byway of a bath that contains water and is processed in a suitable manner.The separated polymer film 50/web 54/polymeric material may be burned asfuel, such as in the paper recycling plant, or otherwise be recycled.

Whereas a few specific examples of acceptable methods for forming thelaminates 20, 20′ are discussed above, those of ordinary skill willunderstand that there are a variety of ways in which the laminates canbe constructed. That is, the layers of the laminates 20, 20′ can bejoined using any suitable process or technique. By way of example, andnot limitation, the layers may be joined using adhesive bonding, thermalbonding, or any other chemical or mechanical means. Bonding may beachieved using any suitable process, for example, spraying, rollcoating, extrusion lamination, or any other process.

As alluded to above, the blank 22 can be configured to be part of acontainer or other type of construct, such as the tray 70 shown in FIG.3. In accordance with the first embodiment, the tray 70 is at leastsubstantially leakproof/hermetically sealed. Therefore, it is typicalfor each of the fold lines 28, 32, 38 to be a score line that does notform a hole in the blank 22/laminate 20. In accordance with alternativeembodiments of the present invention, the fold lines 28, 32, 38 can beformed in any conventional manner, and one or more of them can beomitted.

As best understood with reference to FIG. 3, the tray 70 of the firstembodiment includes the blank 22 and a frame 72 that holds the blank inan erected configuration. The frame 72 is typically constructed ofpolymeric material; however, the frame can also be constructed of othertypes of materials. Referring also to FIG. 4, which schematically showsthe frame 72 in isolation, the frame 72 includes strip-like cornerelements 74 that extend downwardly and somewhat inwardly (obliquely, ormore specifically acutely) from a substantially rigid band 76 of theframe 72. In accordance with the first embodiment, the corner elements74 advantageously hermetically seal the corners of the tray 70, as willbe discussed in greater detail below.

As best understood with reference to FIG. 3, the panels 24, 30, 26 (FIG.1A) of the blank 22 (FIG. 1A) and the strip-like corner elements 74 ofthe frame 72 together extend around and define a substantially leakproofcavity 78 of the tray 70. Typically the polymer film 50 (FIGS. 2A and2B) of the blank is fluid impervious and in opposing face-to-facerelation with the cavity 78. The base panel 24 of the tray 70 optionallyincludes an embossed area 80 that is partially defined by a score-likeline 82 in the base panel 24. The embossed area 80 of the base panel 24protrudes slightly into the cavity 78 of the tray 70, and it can help torigidify the tray.

FIG. 5 is a schematic cross-sectional view of the tray 70 taken alongline 5-5 of FIG. 3, with only the cross-section being shown. As bestunderstood by referring also to FIG. 3, the tray 70 typically includes amulti-tiered rim 84. The rim 84 extends around and defines an opening tothe cavity 78 of the tray 70. In accordance with the first embodiment,the upper portion of the rim 84 is defined by the band 76 of the frame72, and the lower portion of the rim 84 is defined by the flangeportions 34 a-34 d of the blank 22. As best understood with referencedto FIG. 5, the two tiers of the rim 84 are partially defined by anupright panel or section 85 of each of the flange portions 34 a-34 d ofthe blank. A lower flange 81 extends outwardly from the upper edge ofthe respective side panel 30 to the lower edge of the upright section85. An upper flange 83 extends outwardly from an upper edge of theupright panel or section 85. All or some of the upper flange 83 can beomitted. Each upright section 85 includes an upright inner shoulder 92.As will be discussed in greater detail below, the band 76 is typicallyadhered to the upper surfaces of the flanges 81, 83 and the innershoulder 92, so that the band includes a flat upper surface positionedabove the upper surfaces of the flanges 81, 83, and a cover, lid or thelike can be sealed to the upper surface of the band. As will also bediscussed in greater detail below, typically the band 76 is thickerabove the lower flange 81 than it is above the upper flange 83, suchthat the lower flange advantageously partially defines a relativelylarge channel for having molding material (e.g., fluid polymericmaterial) flow therein during the injection molding.

FIG. 5 is illustrative of numerous vertical cross sections of the tray70. More specifically, FIG. 5 is illustrative of/representative ofvertical cross-sections taken through each of the side panels 30 andassociated portion of the multi-tiered rim 84. On the other hand, othercross-sectional profiles are also within the scope of the presentinvention. For example, the flange portions 34 a-34 d of the blank canbe shaped and/or sized differently, so that the flange portions 34 a-34d do not extend all the way to the outer edge of the rim 84 of the tray70, or so that the flange portions 34 a-34 d are embedded in the band 76of the frame 72. As another example, the flange portions 34 a-34 d ofthe blank 22, or the like, can extend farther outwardly than the band 76of the frame 72, and the rim 84 can consist substantially solely of theflange portions 34 a-34 d.

As best understood with reference to FIG. 3, the band 76 of the frame 72can optionally include a minor imperfection 86 and pin holes 88. Theminor imperfection 86 and the pin holes 88 result from an exemplaryprocess by which the tray 70 is manufactured. However, the minorimperfection 86 and the pin holes 88 are optional features because itmay be possible to manufacture the tray 70 without forming the minorimperfection 86 and the pin holes 88. Indeed, in one example of thepresent invention, the pins that form the pin holes 88 are omitted, aswill be discussed in greater detail below. Also and as will be discussedin greater detail below, the frame 72 can be injection molded using avalve gate so that any imperfection 86 is minimized. Alternatively, evenif the minor imperfection 86 and the pin holes 88 are formed, steps maybe taken so that the they are removed or otherwise not readily visible.

An acceptable method for manufacturing the tray 70 will be discussed ingreater detail below (e.g., with reference to the mold assembly 130shown in FIG. 8A). Nonetheless, some aspects associated with anexemplary method of manufacturing the tray 70 are illustrated in FIG. 3and will, therefore, now be briefly discussed with reference to FIG. 3.The minor imperfection 86 results from the frame 72 being manufacturedfrom molding material, namely polymeric material, that is injected intoa mold. That is, the imperfection 86 is located at the sole locationwhere the liquid molding material is injected (e.g., via a valve gate).The arrows drawn onto the frame 72 in FIG. 3 schematically illustratethe directions in which some of the fluid molding material flows to formthe frame 72. The arrows drawn onto the frame 72 in FIG. 3 are schematicbecause they would not be seen on a formed tray 70.

In accordance with the first embodiment and referring to FIG. 5, flow ofthe fluid molding material is controlled in a manner that seeks to keepthe band 76 of the frame 72 on top of the flange portions 34 of theblank 22. More specifically, end edges of the flange portions 34 a-34 d(FIG. 1A), namely the protruding features 44 a-44 h (e.g., see theprotruding features 44 a, 44 b identified in FIG. 1B), are respectivelyoverlapped and at least some of the flange portions are optionally heldin a predetermined manner by pins (e.g., see pins 144 shown in FIGS. 8Aand 11B) that respectively cause the pin holes 88 to be formed, so thatthe fluid molding material flows over the flange portions 34 a-34 dduring injection molding, as will be discussed in greater detail below.Even more specifically and as best understood by referring to FIGS. 1Aand 3, the flange portions 34 a-34 d respectively include overlappingend edges 90 a, 90 b, 90 c, 90 d (which are hidden from view by the band76 in FIG. 3 and, therefore, illustrated by dashed lines in FIG. 3). Inthe tray 70 shown in FIG. 3, the end edge 90 a of the flange portion 34a overlaps the adjacent end of the flange portion 34 b, so that the endedge 90 e of the flange portion 34 b is below the flange portion 34 a.Similarly, the end edge 90 b of the flange portion 34 a overlaps theadjacent end of the flange portion 34 c. Likewise, the end edge 90 c ofthe flange portion 34 b overlaps the adjacent end of the flange portion34 d. Lastly, the end edge 90 d of the flange portion 34 c overlaps theadjacent end of the flange portion 34 d.

In accordance with other embodiments of the present invention, differenttechniques can be used to form the band 76 of the frame 72 on top of theflange portions 34 of the blank 22. As one example, the above and belowdiscussed pinning of the overlapping end edges 90 a-90 d can be omitted,and the frame 72 can be formed by injecting the fluid molding materialinto the main cavity of the mold assembly (e.g., mold assembly 130 ofFIG. 8A) at multiple locations. In contrast and in accordance with otheralternative embodiments of the present invention, the band 76 of theframe is not formed on top of the flange portions 34 a-34 d of the blank22. For example, the flange portions 34 a-34 d can be embedded withinthe band 76 or be positioned above the band.

FIG. 6 schematically shows the outer side of a representative corner ofthe tray 70, as viewed generally from below. In accordance with thefirst embodiment, the corner includes an outwardly protruding bulbousportion 100 that is located at the lower end of the corner. Also, arelatively small gap 102, which is defined between the edges of the sidepanels 30 that partially define the corner, extends upwardly from thebulbous portion 100. At the lower end of each corner of the tray 70,outer surfaces of the side panels 30 and intermediate panels 26 definean outwardly curved surface of the bulbous portion 100, and thecorresponding inner surfaces of the side panels 30 and intermediatepanels 26 define a substantially bowl-shaped recess 101 shown in FIG.7B.

FIG. 7A illustrates the inner side of the representative cornerillustrated in FIG. 6, with an upper part of the tray 70 cut away and anadditional upper portion of the strip-like corner element 74 of theframe 72 cut away. FIG. 7B is like FIG. 7A, except that the cornerelement 74 of the frame 72 has been removed. As best understood withreference to FIG. 7A, the strip-like corner element 74 of the frame 72can be characterized as being, or including, a strip that extends alongand at least partially defines the corner of the tray 70, with thisstrip obstructing the gap 102. Referring to FIG. 6 and in accordancewith the first embodiment, a majority of the outer side of the corner isdefined by the paperboard 52 of the blank 22, except that a bead 106(e.g., an elongate, outwardly projecting protrusion) of the associatedstrip-like corner element 74 of the frame 72 protrudes into and fills(e.g., hermetically seals) the gap 102. Similarly and as shown in FIG.6, all of the lower surface of the rim 84 is defined by paperboard 52 ofthe blank 22. Nonetheless, differently configured corners and rims arewithin the scope of the present invention. For example, the lowersurface of the rim 84 can be partially in the form of the band 76 (FIG.3), as will be discussed in greater detail below.

As best understood with reference to FIG. 6, outwardly projecting ribs104 extend upwardly form the bulbous portion 100 and are positioned onopposite sides of the gap 102. For each corner of the tray 70, its bead106 is collinear with the corner's elongate centerline that extendsalong the corners' length, and the bead is spaced apart from (e.g.,centered between) the corner's ribs 104. As shown in FIG. 6, the ribs104 comprise curved portions of the panels 30. The outward surface ofeach rib 104 is an outwardly projecting, convex protrusion of therespective panel 30, with the outwardly projecting protrusion of thepanel being elongate and extending along the respective corner of thetray 70. In accordance with the first embodiment, these outwardlyprojecting protrusions of the panels 30/ribs 104 are not pleats.

As best understood with reference to FIG. 7B, for each rib 104, theinward surface of the associated curved portion of the panel 30 definesa recess 108 that is elongate and extends along the corner of the tray70. In addition and as best understood with reference to FIG. 7A, eachrib 104 further includes a portion of the respective strip-like cornerelement 74 of the frame 72, namely an outwardly projecting, convexprotrusion 110 that is elongate, extends along the corner, and extendsinto the respective recess 108 of the curved portion of the respectivepanel 30.

As best understood with reference to FIG. 3 and primarily with referenceto FIG. 7A, for each interior corner of the tray 70, from top to bottom,the inner side of the corner is smoothly rounded from side to side. Thestrip-like corner element 74 of the frame 72 that extends into thecorner includes an inwardly facing, smooth surface that can becharacterized as having an upper portion 120 and a lower portion 122.The corner element 74 is shaped to contribute to the smooth side-to-sidecurvature of the inner side of the corner of the tray 70. Morespecifically, the upper portion 120 (of the inwardly facing surface ofthe strip-like corner element 74) extends concavely and smoothly betweenthe adjacent side panels 30, and all the way up to the rim 84. The lowerportion 122 (of the inwardly facing surface of the corner element 74)extends smoothly and in somewhat of a concave/bowl-like fashion betweenthe adjacent intermediate panels 26.

The exemplary manner in which the corners of the tray 70 are constructedis advantageous because it avoids pleating, or the like, of the blank22. The avoidance of the pleating, or the like, and the sealing of therelatively small gap 102 (FIGS. 6, 7A and 7B) can play an advantageousrole with respect to the tray 70 being hermetically sealed and,therefore, leakproof. More specifically, the outwardly bulbous portion100 (FIG. 6) in combination of the outwardly projection ribs 104 (FIG.6) helps to provide a pleat-free corner with a smoothly-radiusedinterior surface, without there being an undercut. This lack of anundercut allows the tray 70 to be easily removed from the mold (e.g.,mold assembly 130 of FIG. 8A) in which it is formed, as will bediscussed in greater detail below. As an example of an additionaladvantage that is discussed in greater detail below, the outwardlybulbous portion 100 and the outwardly projection ribs 104 help to definerelatively large channels for accommodating flowing molding materialduring the injection molding. Notwithstanding the foregoing, otherconfigurations of the corners and other features are also within thescope of the present invention, and in some applications the tray 70 maynot need to be, and therefore may not be, constructed to be leakproof.

FIG. 8A schematically illustrates a forming tool (e.g., mold assembly130) that can be used in the manufacture of the tray 70, in accordancewith the first embodiment. The mold assembly 130 is in an openconfiguration in FIG. 8A, and it includes a male mold 132 and a femalemold 134. The male mold 132 includes an outer mold 136 to which a noseunit 138 is movably mounted. A group of springs 140, only two of whichare schematically shown in FIG. 8A, urge the nose unit 130 toward thefemale mold 134. The nose unit 138 typically includes one or moreflushly mounted vacuum cups 142 that are open at the face of the noseunit 138. The one or more vacuum cups 142 are connected to a suctionsource (not shown) so that a suction can be supplied to the vacuum cups142 in a controlled manner, as will be discussed in greater detailbelow. Optionally, four securing elements, such as securing pins 144,protrude from the male outer mold 136 for aiding in the forming of thetray 70, as mentioned above and as will also be discussed below. Therecan be a greater or lesser number of securing elements (e.g., securingpins 144), and in some situations they can be completely omitted.

A port 146 (e.g., with a valve gate) is defined in the male outer mold136, or otherwise provided, for injecting fluid molding material, or thelike, into the mold assembly 130 to form the frame 72. In one example,the port 146 is in the form of, or includes, a valve gate. Morespecifically, a valve stem is moved to open and close the port 146 in amanner that seeks to minimize shearing of solidified molding material atthe imperfection 86 (FIG. 3) caused by the port 146. This canadvantageously aid in the formation of a smooth surface on the band 76of the frame 72.

The female mold 134 includes an outer mold 150 to which an embossingunit 152 is movably mounted. A group of springs 154, only two of whichare schematically shown in FIG. 8A, urge the embossing unit 152 towardthe male mold 132. A group of locating pins 156 are typically mounted tothe female outer mold 150 in an arrangement that is for helping toposition the blank 22 in a predetermined location, as will be discussedin greater detail below. The flat blank 22 is schematically illustratedby dashed lines in FIG. 8A. The embossing unit 152 typically includesone or more flushly mounted vacuum cups 158 that are open at the face ofthe embossing unit 152. The one or more vacuum cups 158 are connected toa suction source (not shown) so that a suction can be supplied to thevacuum cups 158 in a controlled manner, as will be discussed in greaterdetail below.

The shapes of the surfaces of the female outer mold 150 that define themain cavity of the female outer mold 150 and the face of the embossingunit 152 respectively correspond to the shapes of the exterior surfacesof the tray 70. As shown in FIG. 9, the female outer mold 150 includesinterior corners that are positioned in the main cavity of the femaleouter mold 150. Each of these interior corners includes a subcavity 160that is at least partially in the form of a concavity. The subcavities160 are respectively proximate the corners of the centrally open base161 of the female outer mold 150. The central opening of the base 161 isfor being in receipt of the embossing unit 152 (e.g., see FIG. 8A). Thesubcavities 160 are bowl-shaped recesses that partially define the maincavity of the female outer mold 150 and the interior corners of thefemale outer mold 150. The subcavities 160 are for at least partiallyforming the outwardly bulbous portions 100 (FIG. 6) of the corners ofthe tray 70.

Each of the interior corners in the main cavity of the female outer mold150 also includes a pair of spaced apart, elongate indentions 162 thatrespectively extend from the subcavities 160 all the way to the tieredshoulder 164 of the female outer mold 150. The shoulder 164 extends allthe way around the main cavity of the female outer mold 150, and can becharacterized as defining the opening to the main cavity of the femaleouter mold 150. The shoulder 164 is tiered/has a series of step-likesurfaces for at least partially forming the lower surface of the rim 84(e.g., see FIG. 5) of the tray 70; more specifically for at leastpartially forming (e.g., at least partially controlling folding of) thelower flange 81, upper flange 83 and upright section 85 of the rim 84.The elongate indentions 162 are for at least partially forming theoutwardly projecting ribs 104 (FIG. 6) of the corners of the tray 70.Between each pair of elongate indentions 162 is an elongate centralregion 166 that projects into the main cavity of the female outer mold150. The elongate central regions 166 respectively extend from thesubcavities 160 all the way to the shoulder 164 of the female outer mold150. The central regions 166 are respectively for at least partiallyforming the centerlines of the corners of the tray 70. Differentlyshaped corners within the main cavity of the female outer mold 150 arealso within the scope of the present invention.

An exemplary method of forming the tray 70 using the mold assembly 130and the blank 22 is described in the following. As best understood withreference to FIGS. 8A and 9, in an initial step, the flat blank 22(shown by dashed lines in FIGS. 8A and 9) is placed against the femalemold 134 so that the locating pins 156 are arranged around, and engage,the periphery of the blank 22. That is, the locating pins 156 help tofacilitate proper placement of the blank 22. The blank 22 is held inthis proper placement by virtue of the embossing unit 152 being in itsoutward configuration, and suction being supplied to the vacuum cups158, so that the vacuum cups hold the blank. As a result, the blank 22is securely held against the face of the embossing unit 152, as ispartially schematically illustrated by the dashed-line showing of theflat blank 22 in FIG. 8A.

While the blank 22 is being held in place against the face of theembossing unit 152 as a result of suction being supplied to the vacuumcups 158, the entire female mold 134 is advanced toward the stationaryouter mold 136 of the male mold 132 under the action of a hydraulicpress (not shown), or the like. Alternatively, the male mold 132 couldbe moved toward the female mold 134. As the flat blank 22 comes intocontact with the nose 138, the base panel 24 of the blank 22 issandwiched between the face of the nose 138 and the face of theembossing unit 152, and the springs 140, 154 compress. The face of thenose 138 and the face of the embossing unit 152 are typicallycooperatively shaped so that sandwiching of the blank 22 between thenose 138 and the embossing unit 152 causes the embossed area 80 (FIGS. 3and 5) to at least eventually be formed in the base panel 24 of theblank 22. As the mold assembly 130 further closes, the base panel 24 issecurely held between the nose 138 and the embossing unit 152, andinteraction between the blank 22 and the mold assembly 130 causesfolding to occur along the fold lines 28, 32, 38 of the blank so thatthe blank becomes erected. As a result, the blank 22 is in an erectedstate within the main cavity of the mold assembly 130 when the moldassembly achieves the fully closed configuration schematicallyillustrated in FIG. 10A.

Prior to the mold assembly reaching the closed configuration shown inFIG. 10A, while the mold assembly 130 is still closing, the differencesbetween the lengths of the protruding features 44 a-44 h (FIGS. 1A and1B) can be utilized to facilitate the desired overlapping of the endedges of the flange portions 34 a-34 d, which was discussed above withreference to FIG. 3.

FIG. 10B is a schematic, isolated top plan view of a portion of arepresentative corner of the blank 22 with side panels 30 foldedupwardly. FIG. 10B illustrates an intermediate step of the blank 22being erected by closing the blank in the mold assembly 130. FIG. 10B isrepresentative of the blank 22 having been partially forced into thecavity of the female outer mold 150. As shown in FIG. 10B, since theprotruding feature 44 f is longer than the protruding feature 44 b, theprotruding feature 44 f extends farther outwardly than the protrudingfeature 44 b. That is, when the blank 22 has been partially forced intothe cavity of the female outer mold 150 to the degree schematicallyshown in FIG. 10B, the longer protruding features 44 e, 44 f, 44 g, 44 hprotrude farther outwardly than the shorter protruding features 44 a, 44b, 44 c, 44 d.

FIG. 10C is like FIG. 10B, except that the blank 22 is schematicallyshown as having been farther forced into the cavity of the female outermold 150, so that the longer protruding feature 44 f is being abutted bythe shoulder 164 of the female outer mold 150 (the shoulder 164 is shownin greater detail in FIGS. 8A, 8B and 9). The shoulder causes the longerprotruding feature 44 f to move (e.g., fold) into superposedrelationship with the shorter protruding feature 44 b. That is, whilethe mold assembly 130 is closing, because of their greater length, thelonger protruding features 44 e, 44 f, 44 g, 44 h engage the shoulder164 of the female outer mold 150 before the shorter protruding features44 a, 44 b, 44 c, 44 d can engage the shoulder 164. As a result, thelonger protruding features 44 e, 44 f, 44 g, 44 h respectively move(e.g., fold) into superposed relationships with the shorter protrudingfeatures 44 a, 44 b, 44 c, 44 d, so that the shorter protruding features44 a, 44 b, 44 c, 44 d are respectively positioned between the longerprotruding features 44 e, 44 f, 44 g, 44 h and the female outer mold150. As a result, when the resulting tray 70 is viewed from above, theshorter protruding features 44 a, 44 b, 44 c, 44 d respectively overlapthe longer protruding features 44 e, 44 f, 44 g, 44 h, as schematicallyillustrated in FIG. 3 by the broken-line showing of the overlapping endedges 90 a, 90 b, 90 c, 90 d of the shorter protruding features 44 a, 44b, 44 c, 44 d of the flange portions 34 a-34 d.

As best understood with reference also to FIG. 8A, in the configurationillustrated by FIG. 10C, the female mold 134 has been advanced so thatthe mold assembly 130 is in the fully closed configuration shown in FIG.10A, except that the male outer mold 136 is still extended from the noseunit 138 so that male outer mold 136 does not interfere with theabove-discussed folding of the longer protruding features 44 e, 44 f, 44g, 44 h. That is and in accordance with the first embodiment, theembossing unit 152 achieves its retracted configuration (shown in FIG.10A) with respect to the female outer mold 150 before the nose unit 138achieves its retracted configuration (shown in FIG. 10A) with respect tothe male outer mold 136. This difference can be achieved by having thegroup of springs 140 of the male mold 132 being stronger than the groupof springs 154 of the female mold 134.

After the configuration schematically illustrated by FIG. 10C, the moldassembly 134 is fully closed so that the flange portions 34 a-34 e(FIG. 1) are partially folded, such as by at least partially beingbent/folded along the outer fold lines 36 (FIG. 1). In the fully closedconfiguration of the mold assembly 130 shown in FIG. 10A, channels(e.g., see FIGS. 11A, 11B and 13), which are for having a moldingmaterial (e.g., fluid polymeric material) flow therein, are definedwithin the mold assembly. The channels, which are for having the moldingmaterial flow therein are discussed in the following, in accordance withthe first embodiment. These channels are at least primarily definedbetween the partially erected blank 22 and the male mold 132. Thesechannels at least generally correspond to the shape of the frame 72,although at least some of the channels expand during the injectionmolding due to movement of respective portions of the blank 22 while themolding material flows within the channels. More specifically and forexample, as fluid molding material (e.g., fluid polymeric material) isforced under pressure into initial channels, at least some of theinitial channels expand and are transformed into resultant channels dueto movement of respective portions of the blank 22 while the fluidmolding material flows within the channels. This includes liquid moldingmaterial flowing with sufficient force to cause portions of the blank 22to be pressed against respective surfaces of the female mold 134 (e.g.,FIG. 9), so that respective parts of the blank are forced against theshoulder 164, and into the subcavities 160 and elongate indentations162.

In one example, the liquid molding material is a polymer that isinjected into the closed mold assembly 130 via the port 146, with theinjected polymer being at a temperature of about 500 degrees Fahrenheitand a pressure of approximately 2000 lb/in². The injection temperatureand pressure may depend upon the polymer that is injected, and a widevariety of polymers, temperatures and pressures are within the scope ofthe present invention. For example and not for the purpose of limitingthe scope of the present invention, suitable polymers for being injectedmay be polypropylene, nylon and polyethylene terephthalate (PET). In oneexample, the liquid molding material is polypropylene that is injectedinto the closed mold assembly 130 via the port 146, with the injectedpolypropylene being at a temperature of about 450 degrees Fahrenheit anda pressure of approximately 1750 lb/in². The polymeric liquid moldingmaterial that is injected into the closed mold assembly 130 via the port146 may include one or more additives, such as short glass fibers.Impregnating the polymeric liquid molding material with short glassfibers can help to advantageously control/minimize shrinkage of thesolidifying polymeric material. The polymeric liquid molding materialmay include about 30% glass fibers by weight, although other amounts andother additives are also within the scope of the present invention.

More specifically, the flange portions 34 a-34 c (FIG. 1A) are typicallyonly partially folded during closing of the mold assembly 130, such thatthe flowing molding material in the mold assembly 130 at least completesthe forming and/or bending and/or folding of the flange portions (e.g.,by pressing them against the female mold's shoulder 164) that isnecessary to provide the multi-tiered rim 84 (FIG. 5). Similarly, whenthe mold assembly 130 is closed and prior to the injecting of themolding material, the recesses 101, 108 (e.g., FIG. 7B) in the blank arenot yet formed or are only partially formed, such that the flowingmolding material in the mold assembly 130 at least completes the formingand/or bending and/or folding that creates the recesses 101, 108, bypressing the respective portions of the blank into the female mold'ssubcavities 160 (FIG. 9) and elongate indentations 162 (FIG. 9).

Stated different and in accordance with one example of the firstembodiment, in each interior corner of the female outer mold 150, theelongate indentations 162 advantageously receive respective portions ofthe blank 22 and thereby help to define relatively large channels foraccommodating the flow of molding material. These relatively largechannels seek to help keep the fluid molding material in predeterminedareas, namely it causes the strip-like corner elements 74 of the frame72 to be formed, for the most part, within the cavity 78 of the tray 70.As best understood with reference to FIGS. 6 and 7A, these relativelylarge channels respectively correspond to the elongate, relatively thickportions of the frame's corner elements 74 that are respectively part ofthe outwardly projecting ribs 104.

Stated different and in accordance with another example of the firstembodiment, the forceful flowing of the molding material can also forceat least portions of the flange potions 34 a-34 d of the blank 22against respective portions of the shoulder 164 of the female mold 134.That is, as the polymeric fluid flows in the channels, it pushesrespective portions of the paperboard 52, or the like, of the blank 22into intimate contact with respective portions of the female mold 134.

For example, and as can be best understood also with reference to FIGS.1B and 10C, FIG. 11A schematically illustrates, by way of an arrow, theinjected molding material flowing in a downstream direction through arepresentative channel at an upper interior corner of the mold assembly130. As shown in FIG. 11A, the channel is defined between the shoulder164 (which is part of the female outer mold 150) and the male outer mold136. The protruding features 44 f, 44 b can be characterized as beingwithin the channel, or the channel can alternatively be characterized asbeing defined between the protruding features 44 f, 44 b and the maleouter mold 136. The protruding features 44 f, 44 b are overlapped, andthe edge 90 b of the shorter protruding feature 44 b is positionedbetween the longer protruding feature 44 f and the channel. With respectto the portion of the channel shown in FIG. 11A, as the injected moldingmaterial flows through the upstream portion of the channel it forces theshorter protruding feature 44 b against the shoulder 164. The flow ofthe molding material through the intermediate portion of the channelforces the end section of the shorter protruding feature 44 b againstthe end section of the longer protruding feature 44 f, whichadvantageously seeks to keep the flowing molding material from liftingthe edge 90 b in a manner that might allow the molding material to flowon the wrong side of the flange portions 34 a-34 d of the blank 22. Asecuring pin 144 (FIGS. 8A and 11B) is not shown in the channel of FIG.11A because, for example, the securing pins 144 can be omitted.

As best understood with reference to FIGS. 1 and 3 and the portion ofthe representative corner schematically shown in FIG. 11B, the securingpins 144 (which are optional and may be omitted) are respectivelyproximate, yet distant from the end edges 90 a-90 d. The securing pins144 may respectively engage and hold the flange portions 34 b-34 d ofthe blank 22 against the shoulder 164 of the female outer mold 150 tohelp define the channels in which the fluid molding material flows, andto maintain the proper positioning of the molding material (i.e., frame72) with respect to the blank 22. From the perspective of the flowingmolding material, for each pair of closely adjacent end edges of theflange portions 34 a-34 d, typically only the downstream flange portionis pinned down by a securing pin 144. That is, typically the securingpins 144 engage only the flange portions 34 b-34 d at positions adjacentto the longer protruding features 44 e, 44 f, 44 g, 44 h. Depending, forexample, upon the pressure at which the fluid molding material isinjected and/or the number of, or location of, the injection ports(e.g., see the port 146 in FIG. 8A) at which the fluid molding materialis injected and/or the overlapping between the protruding features 44a-44 h, the securing pins 144 can be omitted. Typically the securingpins 144 will be omitted, since they can cause imperfections and/orcause the tray 70 to stick to the male mold 132. That is, variouslyconfigured mold assemblies 130, trays 70 and other features are withinthe scope of the present invention.

More specifically regarding the channels in which the frame's band 76 ofthe first embodiment is formed, there is a relatively large innerchannel and a relatively small outer channel. As can be best understoodwith reference to FIG. 5, the portion of the band 76 that is to theright of an imaginary vertical line that extends along the shoulder 92and to the top of the band 76 corresponds to the relatively large innerchannel, and the remainder of the band 76 corresponds to the relativelysmall outer channel. During the injection molding, the fluid moldingmaterial primarily flows along the relatively large inner channel, andflows from the relatively large inner channel outwardly to therelatively small outer channel. This outwardly flowing seeks to helpkeep the molding material in predetermined areas, namely it helps toforce the flange portions 34 a-34 d against the shoulder 164 of thefemale outer mold 150 in a manner that seeks to prevent the flangeportions 34 a-34 d from folding in the wrong direction (not shown).

As best understood with reference to FIG. 11B, the tips of the securingpins 144 extend into the relatively large outer channel. As can be bestunderstood with reference to FIG. 6, the upright section 85 of theflange portions 34 a-34 d is closer to the outer edge of the rim 84 inthe corners of the tray 70, so that the width of the relatively largeinner channel is larger in the corners of the tray 70 than elsewhere.This allows for the tips of any securing pins 144 to extend into therelatively large inner channel at the corners of the tray 70 withoutunduly restricting the flow of the fluid molding material. Also so asnot to unduly interfere with the flow, the tips of the securing pins 144are positioned closer to the outer side of the relatively large innerchannel, as shown in FIG. 11B.

After the liquid molding material solidifies so that the tray 70 isformed within the mold assembly 130, the mold assembly is opened. Whilethe mold assembly is being opened, suction is supplied to the vacuumcups 142 of the male mold 132, and not to the vacuum cups 158 of thefemale mold 134, so that the formed tray 70 is held by suction to thenose 138 of the male mold 132. The tray 70 can be readily removed uponcessation of the suction. Thereafter, the mold assembly 130 can be usedto manufacture another tray 70.

As mentioned above, the corners of the tray 70 are typically constructedin a manner that seeks to make the tray leakproof. In addition, thecorners are typically formed so that the tray 70 does not include anundercut that inhibits the tray 70 from being removed from the moldassembly 130. Notwithstanding the foregoing, other configurations of thecorners and tray 70 are also within the scope of the present invention.For example, the tray 70 could be modified so that it is not leakproof,for applications that do not require leakproofness.

In accordance with the first embodiment, the film 50 of the laminate20/blank 22 and the molding material (e.g., polymeric material) fromwhich the frame 72 are constructed are selected to be compatible, sothat there is good adhesion between the frame 72 and the film 50 of theblank 22. In one example, both the frame 72 and the film 50 are apolyolefin, such as polypropylene. As another example, each of the frame72 and the film 50 can be nylon or polyethylene terephthalate. A widevariety of other polymers can also be used, as discussed in greaterdetail below. When the film 50 is a coextrusion, it is the outer-mostlayer of the film 50 that is selected to be compatible with the frame 72so that there is good adhesion therebetween. In an alternativeembodiment of the present invention, such as where the materials areselected so that there is less adhesion between them (i.e., lessadhesion between the flame 72 and the blank 22), the blank or portionsthereof (e.g., edges of the blank) can be at least partially embeddedin, or encapsulated by, the frame in a manner such that the blank andthe frame are nonetheless fixedly attached to one another, if desired.

Initially forming the blank 22 with the fold lines 28, 32, 38, which canbe score lines, seeks to aid in the erecting of the blank within theclosing mold assembly 130. However, one or more of the score lines(e.g., fold lines 28, 32, 38) could be omitted from the blank 22, inwhich case it may be necessary to close the mold assembly relativelyslowly, in an effort to ensure that the blank is properly erectedtherein. For example, the flat blank 22 schematically shown in FIGS. 8Aand 9 could completely lack fold/score lines. That is, a variety ofdifferent blanks are within the scope the scope of the presentinvention. Likewise, a variety of different mold assemblies are withinthe scope of the present invention. Therefore, a variety of differentconstructs (e.g., blanks, trays, cartons and other containers) are alsowithin the scope of the present invention.

In accordance with the first embodiment, after the tray 70 is formed,food can be placed in the tray's cavity, and then the tray's opening canbe closed in a leakproof manner, such as with a cover in the form of apolymeric overwrap that can be advantageously heat sealed to the flatupper surface of the band 76 of the frame 72. For example, FIG. 12schematically illustrates the tray 70 of FIG. 3 containing food 170 andclosed with a polymer film 172 that is heat sealed to the substantiallyflat, upwardly facing surface of the band 76 of the frame 72. FIG. 12 isschematic because the food 170, which is hidden from view, is shown bydashed lines, and the thickness of the overwrap/polymer film 172 thatcloses the tray 70 is exaggerated. Alternatively, the tray 70 can beclosed with lids made of paperboard, foil or any other suitablematerial. A variety of mechanisms for closing the opening of the tray70, such as in a leakproof manner, are within the scope of the presentinvention.

Referring back to FIG. 11B, it schematically illustrates a line ofengagement 180 that exists between the outer mold 136 and nose unit 138of the male mold 132. The line of engagement 180 may in some situationsresult in the formation of parting lines (not shown) in the cornerelements 74 of the polymeric frame 72, with the parting linescorresponding with/being in opposing face-to-face contact with therespective portions of the line of engagement 180 while the moldassembly 130 is closed. The parting lines are optional and may beomitted.

FIG. 13 schematically illustrates a line of engagement 380 that existsbetween an outer mold 336 and nose unit 338 of a male mold 332 of asecond exemplary embodiment of the present invention. The secondembodiment is like the first embodiment, except for variations noted andvariations that will be apparent to those of ordinary skill in the art.Therefore, reference characters for elements of the second embodimentthat are at least generally like elements of the first embodiment arethe same, except that they are incremented by two hundred.

FIG. 13 is like FIG. 11B, except, for example, that in FIG. 13 an entirelength of the representative corner element 274 of the polymeric frame272 is shown, and the male mold 332 of the second embodiment has beensubstituted so that the line of engagement 380 between the male outermold 336 and the nose unit 338 is located in a manner that seeks toprevent formation of a parting line in the corner element 274. That is,the line of engagement 380 between the male outer mold 336 and the noseunit 338 typically will not cause a parting line in the corner elements274 of the polymeric frame 272 of the second embodiment. Also, thesecuring pin 144 has been omitted from FIG. 13, for example since thesecuring pins 144 are optional and may typically be omitted.Alternatively, the securing pins could be included in the secondembodiment.

FIG. 13 illustrates the fully closed mold assembly 330, in accordancewith the second embodiment. In this fully closed configuration of thesecond embodiment: the male mold 332 extends into the cavity of thefemale mold 334; the lines of engagement 380 between the male outer mold336 and the nose unit 338 of the male mold are distant from all parts ofthe polymeric frame 272 in a manner that seeks to avoid the formation ofparting lines; the nose unit 338 of the male mold is in a retractedconfiguration with respect to the male outer mold 336; and the embossingunit 352 of the female mold 334 is in a retracted configuration withrespect to the female outer mold 350.

FIG. 14 is an isolated pictorial view of the male outer mold 336 inaccordance with the second embodiment. The male outer mold 336 includesa central cavity 336 a, corners 336 b, and projections 336 c thatextends the corners.

FIG. 15 is an isolated pictorial view of the nose unit 338 (e.g., innermold) of the male mold 332 in accordance with the second embodiment. Thenose unit 338 includes corners with recesses 338 a for respectivelybeing in receipt of the projections 336 c of the male outer mold 336during the retracted configuration.

As with the first embodiment, the nose unit 338 of the second embodimentis movably mounted to the male outer mold 336 for moving between anextended configuration and a retracted configuration. Exemplary aspectsof the mold assembly 330 of the second embodiment being in its closedconfiguration, which is shown in FIG. 13 and includes the nose unit 338being in its retracted configuration, are described in the following.The nose unit 338 is at least partially within the cavity 336 a of themale outer mold 336 so that the projections 336 c of the male outer mold336 are respectively positioned in the recessed corners 338 a of thenose unit 338, so that the projections 336 c extend at least partiallyaround the nose unit 338. As a result, the corners 336 b/projections 336c of the male outer mold 336 are respectively positioned between thenose unit 338 and the interior corners of the female outer mold 350(e.g., see FIG. 9, which shows that each of the interior corners of thefemale outer mold 150 includes a central region 166 between elongateindentations 162). As best understood with reference to FIG. 13, thechannels, which are for having the molding material (e.g., fluidpolymeric material) flow therein during the forming of the cornerelements 274 of the polymeric frame 272 are therefore defined solelybetween the corners 336 b/projections 336 c of the male outer mold 336and the interior corners of the outer mold 350 (i.e., between thecorners 336 b/projections 336 c and those portions of the blank 22 thatare in the interior corners of the outer mold 350). In FIG. 13, therepresentative corner element 274 that is shown is schematicallyrepresentative of one of the injection-molding channels that is definedbetween the corners 336 b/projections 336 c and the portion of the blank22 in the respective interior corner of the outer mold 350.

FIG. 16 illustrates a blank 422 according to a third embodiment of thepresent invention. The third embodiment can be like each of the firstand second embodiments, except for variations noted and variations thatwill be apparent to those of ordinary skill in the art. Referencecharacters for elements of the third embodiment that are at leastgenerally like elements of the first embodiment are the same, exceptthat they are incremented by four hundred.

The blank 422 includes flaps/side panels 430 a-430 d that are foldablyconnected to a base panel 424, such as at fold line(s) 432. Theflaps/side panels 430 a-430 d respectively include protruding features444 a-444 h which respectively protrude into the corner gaps 440. Thelonger protruding features 444 e, 444 f, 444 g, 444 h are longer thanthe shorter protruding features 444 a, 444 b, 444 c, 444 d forfacilitating the above-discussed predetermined overlapping of theprotruding features in a tray (e.g., tray 70).

In addition, the protruding features 444 a, 444 b, 444 g, 444 h protrudeaway from a latitudinal axis 401 of the blank 422. This protruding canhelp to facilitate proper positioning of the flange portions 434 a, 434c in the closed mold assembly 130. This protruding is defined by endsections of the edges 443 a, 443 c of the flaps/side panels 430 a, 430c. In this regard, for each end section of the edges 443 a, 443 c, afirst portion of the end section extends obliquely to, and away from,the latitudinal axis 401, and an adjacent second portion of the endsection extends obliquely to, and toward, the latitudinal axis 401.

Similarly, the protruding features 444 c, 444 d, 444 e, 444 f protrudeaway from a longitudinal axis 402 of the blank 422. This protruding canhelp to facilitate proper positioning of the flange portions 434 b, 434d in the closed mold assembly 130. This protruding is defined by endsections of the edges 443 b, 443 d of the flaps/side panels 430 b, 430d. In this regards, for each end section of the edges 443 b, 443 d, afirst portion of the end section extends obliquely to, and away from,the longitudinal axis 402, and an adjacent second portion of the endsection extends obliquely to, and toward, the longitudinal axis 402.

Also, the flap/side panel 430 a includes a central protruding feature403 that helps to facilitate proper positioning of the flange portion434 a in the closed mold assembly 130, so that the flange portion 434a/protruding feature 403 is positioned adjacent to the port 146 (FIG.8A) through which molding material is injected into the closed moldassembly 130 to form the frame 72, or the like.

FIG. 17 is schematic, and it is like FIG. 5, except that the crosssection of FIG. 17 is taken through a tray formed from the blank 422(FIG. 16), in accordance with the third embodiment. FIG. 17 isillustrative of cross sections taken distant from the outwardlyprotruding features 403, 444 a-444 h of the tray 470 of the thirdembodiment. In contrast, FIG. 5 is schematically illustrative of crosssections taken through the tray 470 of the third embodiment at locationsthat are proximate the outwardly protruding features 403, 444 a-444 h.In contrast to what is shown in FIG. 5, the multi-tiered rim 484 of thetray 470 of the third embodiment does not include the upper flange 83(FIG. 5) in the areas that do not include the outwardly protrudingfeatures 403, 444 a-444 h, and a handle-shaped portion of the band 476of the frame 472 takes the place of the omitted upper flange (e.g.,upper flange 83 in FIG. 5). Similarly, the upright section 485 and otherportions of the multi-tiered rim 484 may be omitted.

As mentioned above, the tray 70, is one example of a construct (e.g.,container, sleeve or other construct) of the present invention. Asalluded to above, any of the various constructs of the present inventionmay optionally include one or more features that alter the effect ofmicrowave energy during the heating or cooking of a food item that isassociated with the construct. For example, the construct may be formedat least partially from (e.g., the web 54 and/or layer of microwaveinteractive material 58 shown in FIGS. 2A and 2B can include) one ormore microwave energy interactive elements (hereinafter sometimesreferred to as “microwave interactive elements”) that promote browningand/or crisping of a particular area of the food item, shield aparticular area of the food item from microwave energy to preventovercooking thereof, or transmit microwave energy towards or away from aparticular area of the food item. Each microwave interactive elementcomprises one or more microwave energy interactive materials or segmentsarranged in a particular configuration to absorb microwave energy,transmit microwave energy, reflect microwave energy, or direct microwaveenergy, as needed or desired for a particular construct and food item.

The microwave interactive element may be supported on a microwaveinactive or transparent substrate (e.g., such as, but not limited to,the paperboard 52 or polymer film 50 shown in FIGS. 2A and 2B) for easeof handling and/or to prevent contact between the microwave interactivematerial and the food item. As a matter of convenience and notlimitation, and although it is understood that a microwave interactiveelement supported on a microwave transparent substrate includes bothmicrowave interactive and microwave inactive elements or components,such constructs are referred to herein as “microwave interactive webs”.

The microwave energy interactive material may be an electroconductive orsemiconductive material, for example, a metal or a metal alloy providedas a metal foil; a vacuum deposited metal or metal alloy; or a metallicink, an organic ink, an inorganic ink, a metallic paste, an organicpaste, an inorganic paste, or any combination thereof. Examples ofmetals and metal alloys that may be suitable for use with the presentinvention include, but are not limited to, aluminum, chromium, copper,inconel alloys (nickel-chromium-molybdenum alloy with niobium), iron,magnesium, nickel, stainless steel, tin, titanium, tungsten, and anycombination or alloy thereof.

Alternatively, the microwave energy interactive material may comprise ametal oxide. Examples of metal oxides that may be suitable for use withthe present invention include, but are not limited to, oxides ofaluminum, iron, and tin, used in conjunction with an electricallyconductive material where needed. Another example of a metal oxide thatmay be suitable for use with the present invention is indium tin oxide(ITO). ITO can be used as a microwave energy interactive material toprovide a heating effect, a shielding effect, a browning and/or crispingeffect, or a combination thereof. For example, to form a susceptor, ITOmay be sputtered onto a clear polymer film. The sputtering processtypically occurs at a lower temperature than the evaporative depositionprocess used for metal deposition. ITO has a more uniform crystalstructure and, therefore, is clear at most coating thicknesses.Additionally, ITO can be used for either heating or field managementeffects. ITO also may have fewer defects than metals, thereby makingthick coatings of ITO more suitable for field management than thickcoatings of metals, such as aluminum.

Alternatively, the microwave energy interactive material may comprise asuitable electroconductive, semiconductive, or non-conductive artificialdielectric or ferroelectric. Artificial dielectrics comprise conductive,subdivided material in a polymeric or other suitable matrix or binder,and may include flakes of an electroconductive metal, for example,aluminum.

In one example, the microwave interactive element may comprise a thinlayer of microwave interactive material that tends to absorb microwaveenergy, thereby generating heat at the interface with a food item. Suchelements often are used to promote browning and/or crisping of thesurface of a food item (sometimes referred to as a “browning and/orcrisping element”). When supported on a film or other substrate, such anelement may be referred to as a “susceptor film” or, simply,“susceptor”. However, other microwave energy interactive elements, suchas those described herein, are contemplated hereby.

As another for example, the microwave interactive element may comprise afoil having a thickness sufficient to shield one or more selectedportions of the food item from microwave energy (sometimes referred toas a “shielding element”). Such shielding elements may be used where thefood item is prone to scorching or drying out during heating.

The shielding element may be formed from various materials and may havevarious configurations, depending on the particular application forwhich the shielding element is used. Typically, the shielding element isformed from a conductive, reflective metal or metal alloy, for example,aluminum, copper, or stainless steel. The shielding element generallymay have a thickness of from about 0.000285 inches to about 0.05 inches.In one aspect, the shielding element has a thickness of from about0.0003 inches to about 0.03 inches. In another aspect, the shieldingelement has a thickness of from about 0.00035 inches to about 0.020inches, for example, 0.016 inches.

As still another example, the microwave interactive element may comprisea segmented foil, such as, but not limited to, those described in U.S.Pat. Nos. 6,204,492, 6,433,322, 6,552,315, and 6,677,563, each of whichis incorporated by reference in its entirety. Although segmented foilsare not continuous, appropriately spaced groupings of such segmentsoften act as a transmitting element to direct microwave energy tospecific areas of the food item. Such foils also may be used incombination with browning and/or crisping elements, for example,susceptors.

Any of the numerous microwave interactive elements described herein orcontemplated hereby may be substantially continuous, that is, withoutsubstantial breaks or interruptions, or may be discontinuous, forexample, by including one or more breaks or apertures that transmitmicrowave energy therethrough. The breaks or apertures may be sized andpositioned to heat particular areas of the food item selectively. Thenumber, shape, size, and positioning of such breaks or apertures mayvary for a particular application depending on type of construct beingformed, the food item to be heated therein or thereon, the desireddegree of shielding, browning, and/or crisping, whether direct exposureto microwave energy is needed or desired to attain uniform heating ofthe food item, the need for regulating the change in temperature of thefood item through direct heating, and whether and to what extent thereis a need for venting.

It will be understood that the aperture may be a physical aperture orvoid in the material used to form the construct, or may be anon-physical “aperture”. A non-physical aperture may be a portion of theconstruct that is microwave energy inactive by deactivation orotherwise, or one that is otherwise transparent to microwave energy.Thus, for example, the aperture may be a portion of the construct formedwithout a microwave energy active material or, alternatively, may be aportion of the construct formed with a microwave energy active materialthat has been deactivated. While both physical and non-physicalapertures allow the food item to be heated directly by the microwaveenergy, a physical aperture also provides a venting function to allowsteam or other vapors to be released from the food item.

It also may be beneficial to create one or more discontinuities orinactive regions to prevent overheating or charring of the construct,for example, where two or more panels abut or overlap. When exposed tomicrowave energy, the concentration of heat generated by the abutted oroverlapped panels may be sufficient to cause the underlying support, inthis case, paperboard, to become scorched. As such, the abutting oroverlapping portions of one or more panels may be designed to bemicrowave inactive, for example, by forming these areas without amicrowave energy interactive material or by deactivating the microwaveenergy interactive material in these areas.

As stated above, any of the above elements and numerous otherscontemplated hereby may be supported on a substrate. The substratetypically comprises an electrical insulator, for example, a polymer filmor material. As used herein the term “polymer” or “polymeric material”includes, but is not limited to, homopolymers, copolymers, such as forexample, block, graft, random, and alternating copolymers, terpolymers,etc. and blends and modifications thereof. Furthermore, unless otherwisespecifically limited, the term “polymer” shall include all possiblegeometrical configurations of the molecule. These configurationsinclude, but are not limited to isotactic, syndiotactic, and randomsymmetries.

The thickness of the film typically may be from about 35 gauge to about10 mil. In one aspect, the thickness of the film is from about 40 toabout 80 gauge. In another aspect, the thickness of the film is fromabout 45 to about 50 gauge. In still another aspect, the thickness ofthe film is about 48 gauge. Examples of polymer films that may besuitable include, but are not limited to, polyolefins, polyesters,polyamides, polyimides, polysulfones, polyether ketones, cellophanes, orany combination thereof. Other non-conducting substrate materials suchas paper and paper laminates, metal oxides, silicates, cellulosics, orany combination thereof, also may be used.

In one example, the polymer film comprises polyethylene terephthalate(PET). Polyethylene terephthalate films are used in commerciallyavailable susceptors, for example, the QWIKWAVE® Focus susceptor and theMICRORITE® susceptor, both available from Graphic PackagingInternational (Marietta, Ga.). Examples of polyethylene terephthalatefilms that may be suitable for use as the substrate include, but are notlimited to, MELINEX®, commercially available from DuPont Teijan Films(Hopewell, Va.), SKYROL, commercially available from SKC, Inc.(Covington, Ga.), and BARRIALOX PET, available from Toray Films (FrontRoyal, Va.), and QU50 High Barrier Coated PET, available from TorayFilms (Front Royal, Va.).

The polymer film may be selected to impart various properties to themicrowave interactive web, for example, printability, heat resistance,or any other property. As one particular example, the polymer film maybe selected to provide a water barrier, oxygen barrier, or a combinationthereof. Such barrier film layers may be formed from a polymer filmhaving barrier properties or from any other barrier layer or coating asdesired. Suitable polymer films may include, but are not limited to,ethylene vinyl alcohol, barrier nylon, polyvinylidene chloride, barrierfluoropolymer, nylon 6, nylon 6,6, coextruded nylon 6/EVOH/nylon 6,silicon oxide coated film, barrier polyethylene terephthalate, or anycombination thereof.

One example of a barrier film that may be suitable for use with thepresent invention is CAPRAN® EMBLEM 1200M nylon 6, commerciallyavailable from Honeywell International (Pottsville, Pa.). Anotherexample of a barrier film that may be suitable is CAPRAN® OXYSHIELD OBSmonoaxially oriented coextruded nylon 6/ethylene vinyl alcohol(EVOH)/nylon 6, also commercially available from HoneywellInternational. Yet another example of a barrier film that may besuitable for use with the present invention is DARTEK® N-201 nylon 6,6,commercially available from Enhance Packaging Technologies (Webster,N.Y.). Additional examples include BARRIALOX PET, available from TorayFilms (Front Royal, Va.) and QU50 High Barrier Coated PET, availablefrom Toray Films (Front Royal, Va.), referred to above.

Still other barrier films include silicon oxide coated films, such asthose available from Sheldahl Films (Northfield, Minn.). Thus, in oneexample, a susceptor may have a structure including a film, for example,polyethylene terephthalate, with a layer of silicon oxide coated ontothe film, and ITO or other material deposited over the silicon oxide. Ifneeded or desired, additional layers or coatings may be provided toshield the individual layers from damage during processing.

The barrier film may have an oxygen transmission rate (OTR) as measuredusing ASTM D3985 of less than about 20 cc/m²/day. In one aspect, thebarrier film has an OTR of less than about 10 cc/m²/day. In anotheraspect, the barrier film has an OTR of less than about 1 cc/m²/day. Instill another aspect, the barrier film has an OTR of less than about 0.5cc/m²/day. In yet another aspect, the barrier film has an OTR of lessthan about 0.1 cc/m²/day.

The barrier film may have a water vapor transmission rate (WVTR) of lessthan about 100 g/m²/day as measured using ASTM F1249. In one aspect, thebarrier film has a water WVTR as measured using ASTM F1249 of less thanabout 50 g/m²/day. In another aspect, the barrier film has a WVTR ofless than about 15 g/m²/day. In yet another aspect, the barrier film hasa WVTR of less than about 1 g/m²/day. In still another aspect, thebarrier film has a WVTR of less than about 0.1 g/m²/day. In a stillfurther aspect, the barrier film has a WVTR of less than about 0.05g/m²/day.

Other non-conducting substrate materials such as metal oxides,silicates, cellulosics, or any combination thereof, also may be used inaccordance with the present invention.

The microwave energy interactive material may be applied to thesubstrate in any suitable manner, and in some instances, the microwaveenergy interactive material is printed on, extruded onto, sputteredonto, evaporated on, or laminated to the substrate. The microwave energyinteractive material may be applied to the substrate in any pattern, andusing any technique, to achieve the desired heating effect of the fooditem.

For example, the microwave energy interactive material may be providedas a continuous or discontinuous layer or coating including circles,loops, hexagons, islands, squares, rectangles, octagons, and so forth.Examples of various patterns and methods that may be suitable for usewith the present invention are provided in U.S. Pat. Nos. 6,765,182;6,717,121; 6,677,563; 6,552,315; 6,455,827; 6,433,322; 6,414,290;6,251,451; 6,204,492; 6,150,646; 6,114,679; 5,800,724; 5,759,422;5,672,407; 5,628,921; 5,519,195; 5,424,517; 5,410,135; 5,354,973;5,340,436; 5,266,386; 5,260,537; 5,221,419; 5,213,902; 5,117,078;5,039,364; 4,963,424; 4,936,935; 4,890,439; 4,775,771; 4,865,921; andRe. 34,683, each of which is incorporated by reference herein in itsentirety. Although particular examples of patterns of microwave energyinteractive material are shown and described herein, it should beunderstood that other patterns of microwave energy interactive materialare contemplated by the present invention.

The microwave interactive element or microwave interactive web may bejoined to or overlie a dimensionally stable, microwave energytransparent support (hereinafter referred to as “microwave transparentsupport”, “microwave inactive support” or “support”) to form theconstruct.

In one aspect, for example, where a rigid or semi-rigid construct is tobe formed, all or a portion of the support may be formed at leastpartially from a paperboard material, which may be cut into a blankprior to use in the construct. For example, the support may be formedfrom paperboard having a basis weight of from about 60 to about 330lbs/ream (i.e., lbs/3,000 ft²), for example, from about 80 to about 140lbs/ream. The paperboard generally may have a thickness of from about 6to about 30 mils, for example, from about 12 to about 28 mils. In oneparticular example, the paperboard has a thickness of about 12 mils. Anysuitable paperboard may be used, for example, a solid bleached or solidunbleached sulfate board, such as SUS® board, commercially availablefrom Graphic Packaging International.

In another aspect, where a more flexible construct is to be formed, thesupport may comprise a paper or paper-based material generally having abasis weight of from about 15 to about 60 lbs/ream, for example, fromabout 20 to about 40 lbs/ream. In one particular example, the paper hasa basis weight of about 25 lbs/ream.

Optionally, one or more portions of the various blanks (e.g., thesubstrate, or more specifically the paperboard 52 which is formed fromcellulosic material) or other constructs described herein orcontemplated hereby may be coated with varnish, clay, or othermaterials, either alone or in combination. The coating may then beprinted over with product advertising or other information or images.The blanks or other constructs also may be coated to protect anyinformation printed thereon. Typically, the margin of the blank will notbe coated or printed with ink or any other material that may have anadverse effect on the adhesion of the frame 72, or the like, to theblank. That is, ink will typically be omitted from the blank in theareas in which the blank and frame 72 overlap. Typically, any ink ormicrowave interactive materials are applied to the blank prior toforming the frame 72 onto the blank/construct/tray, although othersequences can be acceptable.

Furthermore, the blanks or other constructs may be coated with, forexample, a moisture and/or oxygen barrier layer, on either or bothsides, such as those described above. Any suitable moisture and/oroxygen barrier material may be used in accordance with the presentinvention. Examples of materials that may be suitable include, but arenot limited to, polyvinylidene chloride, ethylene vinyl alcohol, DuPontDARTEK™ nylon 6,6, and others referred to above.

Alternatively or additionally, any of the blanks or other constructs ofthe present invention may be coated or laminated with other materials toimpart other properties, such as absorbency, repellency, opacity, color,printability, stiffness, or cushioning. For example, absorbentsusceptors are described in U.S. Provisional Application No. 60/604,637,filed Aug. 25, 2004, and U.S. patent application Ser. No. 11/211,858, toMiddleton, et al., titled “Absorbent Microwave Interactive Packaging”,filed Aug. 25, 2005, both of which are incorporated herein by referencein their entirety. Additionally, the blanks or other constructs mayinclude graphics or indicia printed thereon.

It will be understood that with some combinations of elements andmaterials, the microwave interactive element may have a grey or silvercolor that is visually distinguishable from the substrate or thesupport. However, in some instances, it may be desirable to provide aweb or construct having a uniform color and/or appearance. Such a web orconstruct may be more aesthetically pleasing to a consumer, particularlywhen the consumer is accustomed to packages or containers having certainvisual attributes, for example, a solid color, a particular pattern, andso on. Thus, for example, the present invention contemplates using asilver or grey toned adhesive to join the microwave interactive elementsto the substrate, using a silver or grey toned substrate to mask thepresence of the silver or grey toned microwave interactive element,using a dark toned substrate, for example, a black toned substrate, toconceal the presence of the silver or grey toned microwave interactiveelement, overprinting the metalized side of the web with a silver orgrey toned ink to obscure the color variation, printing thenon-metalized side of the web with a silver or grey ink or otherconcealing color in a suitable pattern or as a solid color layer to maskor conceal the presence of the microwave interactive element, or anyother suitable technique or combination thereof.

As mentioned above, numerous differently configured constructs arewithin the scope of the present invention. As one last example, the tray70 could be configured so that it includes multiple compartments, andthe compartments can respectively include (or be associated with)microwave energy interactive material with different characteristics.More specifically, one of the compartments can include shieldingelements, another compartment can include a susceptor, and anothercompartment can include a transmitting element. Other variations betweencompartments are also within the scope of the present invention.

In accordance with the exemplary embodiments of the present invention,the blanks can be formed from paperboard, corrugated cardboard or othermaterials having properties suitable for at least generally enablingrespective functionalities described above. Paperboard is typically of acaliper such that it is heavier and more rigid than ordinary paper, andcorrugated cardboard is typically of a caliper such that it is heavierand more rigid than paperboard. Typically, at least the side of thepaperboard or cardboard that will be an exterior surface in the cartonerected therefrom will be coated with a clay coating, or the like. Theclay coating can be printed over with product, advertising,price-coding, and other information or images. The blanks may then becoated with a varnish to protect any information printed on the blanks.The blanks may also be coated with, for example, a moisture barrierlayer, on one or both sides. The blanks can also be laminated to orcoated with one or more sheet-like materials.

In accordance with the exemplary embodiments of the present invention, afold line can be any at least somewhat line-like arranged, although notnecessarily straight, form of weakening that facilitates foldingtherealong; and a tear line can be any at least somewhat line-likearranged, although not necessarily straight, form of weakening thatfacilitates tearing therealong. More specifically, but not for thepurpose of narrowing the scope of the present invention, conventionalfold lines include: a crease, such as formed by folding; a score line,such as formed with a blunt scoring knife, or the like, which creates acrushed portion in the material along the desired line of weakness; aslit that extends partially into the material along the desired line ofweakness, and/or a series of spaced apart slits that extend partiallyinto and/or completely through the material along the desired line ofweakness; or various combinations of these features.

It will be understood by those skilled in the art that while the presentinvention has been discussed above with reference to exemplaryembodiments, various additions, modifications and changes can be madethereto without departing from the spirit and scope of the invention asset forth in the following claims.

What is claimed is:
 1. A blank, comprising: a base panel; a pluralityflaps respectively connected to and extending outwardly from the basepanel, wherein the plurality of flaps includes a first flap and a secondflap that is adjacent to the first flap; a gap is defined between thefirst and second flaps, at least an inner portion of the gap becomeswider farther from the base panel, and the first flap has a feature thathas a reducing effect on how width of the gap changes as a function ofincreased distance outwardly from the base panel.
 2. The blank of claim1, wherein the blank is a laminate including a releasable adhesivepositioned between and at least indirectly joining together a substrateand a polymer film.
 3. The blank of claim 1, wherein: at least a portionof the blank comprises microwave energy interactive material, paperboardand polymer film, and the microwave energy interactive material ispositioned between the paperboard and the polymer film.
 4. The blank ofclaim 1, wherein: the feature is a protruding portion of the first flap,the second flap has a protruding portion that has a reducing effect onhow width of the gap changes as a function of increased distanceoutwardly from the base panel, and the protruding portion of the secondflap extends farther into the gap than does the protruding portion ofthe first flap.
 5. The blank of claim 1, wherein the feature is aprotruding portion of the first flap, and wherein the protruding portionof the first flap and the second flap are configured so that theprotruding portion of the first flap and a portion of the second flapare in an overlapping relationship with respect to one another when theblank is erected into a construct in which the gap is at least partiallymaintained.
 6. A construct erected from the blank of claim 5 andincluding an injection-molded frame, wherein: the blank has been erectedso that the gap has been at least partially maintained, and theprotruding portion of the first flap and the portion of the second flapare in an overlapping relationship with respect to one another; and aportion of the frame covers the gap.
 7. The construct of claim 6,wherein the gap is filled by a protruding portion of the frame.
 8. Theblank of claim 1, wherein: the first flap includes an outwardlyextending edge; the second flap includes an outwardly extending edgethat is proximate to the edge of the first flap; at least portions ofthe edges of the first and second flaps are spaced apart from oneanother so that the gap is defined between the edge of the first flapand the edge of the second flap; an outer portion of the gap is fartherfrom the base panel than the inner portion of the gap, an inner portionof the edge of the first flap partially defines the inner portion of thegap, an outer portion of the edge of the first flap at least partiallydefines both the outer portion of the gap and the feature, which has thereducing effect on how the width of the gap changes as a function ofincreased distance outwardly from the base panel, an angle is definedbetween the inner and outer portions of the edge of the first flap, andthe angle is less than 180 degrees so that that the angle at leastpartially provides the reducing effect on how width of the gap changesas a function of distance outwardly from the base panel.
 9. The blank ofclaim 8, wherein the angle, which is defined between the inner and outerportions of the edge of the first flap, is an obtuse angle.
 10. Theblank of claim 8, wherein width of the inner portion of the gap changesat a greater rate, as a function of distance outwardly from the basepanel, than width of the outer portion of the gap.
 11. The blank ofclaim 8, wherein with respect to extending outwardly from the basepanel, the outer portion of the edge of the first flap extendsconvergently with respect to a centerline of the gap.
 12. The blank ofclaim 8, wherein with respect to extending outwardly from the basepanel, the outer portion of the edge of the first flap extendsdivergently with respect to a centerline of the gap.
 13. The blank ofclaim 12, wherein: an inner portion of the edge of the second flappartially defines the inner portion of the gap, an outer portion of theedge of the second flap partially defines the outer portion of the gap,and an angle of less than 180 degrees is defined between the inner andouter portions of the edge of the second flap, and with respect toextending outwardly from the base panel, the outer portion of the edgeof the second flap extends convergently with respect to the centerlineof the gap.
 14. A method of forming a construct from the blank of claim18, the method comprising: closing the blank in a forming tool, so thatthe blank is formed into the construct and the construct is at leastpartially contained in the closed forming tool, wherein the forming toolcomprises a male mold and a female mold, and the closing of the blank inthe forming tool comprises engaging a first part of the male moldagainst a portion of the blank, thereafter using at least the first partof the male mold to at least partially force the portion of the blankinto a cavity of the female mold and thereby partially form theconstruct, thereafter engaging a second part of the male mold against aportion of the blank to further form the construct, and moving the firstpart of the male mold relative to the second part of the male mold at aperiod of time that occurs during the closing of the blank in theforming tool and is after the engaging of the first part of the malemold against the blank.
 15. The method of claim 14, wherein the closingof the blank in the forming tool comprises engaging a first part of thefemale mold against a portion of the blank, thereafter engaging a secondpart of the female mold against a portion of the blank to further formthe construct, and moving the first part of the female mold relative tothe second part of the female at the period of time that occurs duringthe closing of the blank in the forming tool and is after the engagingof the first part of the female mold against the portion of the blank16. The method of claim 14, further comprising forming at least oneinjection-molded feature on the construct while the construct is atleast partially contained in the closed forming tool.
 17. A method offorming a construct from the blank of claim 1, the method comprising:forming the construct, comprising closing the blank in a forming tool,wherein the forming of the construct comprises arranging a first part ofthe construct and a second part of the construct so that there is anoverlapping relationship between the first part and the second part, andan edge of the first part is positioned between the second part and achannel; and forming an injection-molded feature on the construct,wherein the forming of the injection-molded feature includes forcingmolding material to flow in the channel, so that the molding materialflows along the first part, then across the edge of the first part, andthen along the second part.
 18. A blank, comprising: a laminateincluding a releasable adhesive positioned between and at leastindirectly joining together a substrate and a polymer film; a base paneldefined in the laminate; a plurality flaps defined in the laminate, theplurality of flaps being respectively connected to and extendingoutwardly from the base panel, and the plurality of flaps comprises afirst flap and a second flap that is adjacent to the first flap; and agap defined between the first and second flaps.
 19. The blank of claim18, wherein: at least an inner portion of the gap becomes wider fartherfrom the base panel, and the first flap has a feature that has areducing effect on how width of the gap changes as a function ofincreased distance outwardly from the base panel.
 20. The blank of claim18, wherein: the laminate further includes microwave energy interactivematerial, and the microwave energy interactive material is positionedbetween the substrate and the polymer film.
 21. The blank of claim 18,wherein the substrate comprises cellulosic material.
 22. A constructerected from the blank of claim 18 and including at least oneinjection-molded feature that is at least indirectly joined to thepolymer film.
 23. The construct of claim 22, wherein the constructcomprises a container and the injection-molded feature comprises a band.24. The construct of claim 22, wherein: the releasable adhesive providesan adhesive bond between the substrate and the polymer film; theadhesive bond between the substrate and the polymer film has a peelstrength; there is an adhesive bond between the injection-molded featureand the polymer film; the adhesive bond between the injection-moldedfeature and the polymer film has a peel strength; the peel strength ofthe adhesive bond between the substrate and the polymer film is lessthan the peel strength of the adhesive bond between the injection-moldedfeature and the polymer film.
 25. A method of at least partiallydismantling the construct of claim 22, with the method comprising:separating the construct into separate parts, wherein the separating ofthe construct comprises separating the substrate and the polymer filmfrom one another so that the injection-molded feature remains at leastindirectly joined to the polymer film.
 26. The method of claim 25,further comprising recycling at least one of the parts.
 27. The methodof claim 25, wherein the separating of the substrate and the polymerfilm from one another comprises: manually separating the substrate andthe polymer film from one another.
 28. A method of forming a constructfrom the blank of claim 18, the method comprising: closing the blank ina forming tool, so that the blank is formed into the construct and theconstruct is at least partially contained in the closed forming tool,wherein the forming tool comprises a male mold and a female mold, andthe closing of the blank in the forming tool comprises engaging a firstpart of the male mold against a portion of the blank, thereafter usingat least the first part of the male mold to at least partially force theportion of the blank into a cavity of the female mold and therebypartially form the construct, thereafter engaging a second part of themale mold against a portion of the blank to further form the construct,and moving the first part of the male mold relative to the second partof the male mold at a period of time that occurs during the closing ofthe blank in the forming tool and is after the engaging of the firstpart of the male mold against the blank.
 29. The method of claim 28,wherein the closing of the blank in the forming tool comprises engaginga first part of the female mold against a portion of the blank,thereafter engaging a second part of the female mold against a portionof the blank to further form the construct, and moving the first part ofthe female mold relative to the second part of the female at the periodof time that occurs during the closing of the blank in the forming tooland is after the engaging of the first part of the female mold againstthe portion of the blank
 30. The method of claim 28, further comprisingforming at least one injection-molded feature on the construct while theconstruct is at least partially contained in the closed forming tool.31. A method of forming a construct from the blank of claim 18, themethod comprising: forming the construct, comprising closing the blankin a forming tool, wherein the forming of the construct comprisesarranging a first part of the construct and a second part of theconstruct so that there is an overlapping relationship between the firstpart and the second part, and an edge of the first part is positionedbetween the second part and a channel; and forming an injection-moldedfeature on the construct, wherein the forming of the injection-moldedfeature includes forcing molding material to flow in the channel, sothat the molding material flows along the first part, then across theedge of the first part, and then along the second part.